Çimentolu Macun Dolgunun Dayanım ve Mikroyapı Özellikleri; C-Sınıfı Uçucu Külün Etkisi

Öz

Bu çalışmada, sülfürlü atık yerine ağırlıkça %5-15 oranında C-sınıfı uçucu kül (UK) ikamesinin çimentolu macun dolgunun (ÇMD) dayanım ve mikroyapı özelliklerine etkisi incelenmiştir. Bu kapsamda kontrol numuneleri %8,5 bağlayıcı oranında, UK içeren dolgu numuneleri ise %7,5 bağlayıcı oranında hazırlanmıştır. Bu numuneler, tek eksenli basınç dayanımı (TEBD) ve porozite (MIP) testlerine tabi tutulmuştur. Bulgular değerlendirildiğinde, UK içeren tüm ÇMD numunelerinin kontrol numunelerine kıyasla 1,18-3,16 kat daha yüksek TEBD ürettiği gözlemlenmiştir. Dolgunun stabilite (TEBD≥1,0MPa) kriterini tüm numuneler sağlarken, tavan (zemin) tahkimatı (TEBD≥5,0MPa) kriterini sadece %15 UK’lı numuneler sağlamıştır. Porozite (MIP) gelişimleri incelendiğinde, UK ikamesi numunelerin mikroyapı özelliklerini daha fazla iyileştirmiştir. Elde edilen sonuçlardan, C-sınıfı UK kullanımının ÇMD’nin dayanım, duraylılık ve mikroyapı özelliklerinin iyileştirilmesinde oldukça faydalı olduğu sonucuna varılmıştır.

Anahtar Kelimeler

• C-sınıfı Uçucu Kül,Sülfürlü Atık,Tek Eksenli Basınç Dayanımı,Mikroyapı,Çimentolu Macun Dolgu

Strength and Microstructure Properties of Cemented Paste Backfill; Effect of Class-C Fly Ash

Öz

In this study, the effect of Class-C Fly ash (FA) as partial replacement (5-15% by weight) to sulphide tailings on the strength and microstructure properties of cemented paste backfill (CPB) was examined. Within this scope, CPB samples of control were prepared at 8.5 wt.% binder dosage while the other samples containing FA were prepared at 7.5 wt.% binder dosage. These samples were subjected to uniaxial compressive strength (UCS) and porosity (MIP) tests. Findings revealed that all CPB samples containing FA produced notably higher (1.18-3.16 fold) UCSs than control samples. All CPB samples ensured the stability criterion for backfill material (UCS≥1.0MPa), whilst, only the CPB samples containing 15 wt.% FA exceeded the roof (ground) support criterion (UCS≥5.0MPa). When the developments of porosity (MIP) were investigated, the partial replacement of sulphide tailings with FA enhanced the microstructure properties of CPB samples. These results suggest that the utilization of Class-C Fly ash (FA) as partial replacement to sulphide tailings is highly beneficial for the improvement of the strength, durability and microstructure properties of CPB.

Anahtar Kelimeler

• Class-C Fly Ash,Sulphide Tailings,Uniaxial Compressive Strength,Microstructure,Cemented Paste Backfill

Kaynakça

1. [1] European Commission, 2009. Reference document on best available techniques for management of tailings and waste-rock in mining activities, s. 427-435.
2. [2] Erçıkdı, B., Cihangir, F., Kesimal, A., Deveci, H., Eğriboyunoğlu, M., Yılmaz, K. 2017. Macun Dolgunun Çevresel Etkileri: ÇBİ Deneyimi. Uluslararası Madencilik Ve Çevre Sempozyumu (ISME 2017), 27-29 Eylül, Bodrum/Muğla, 359-375.
3. [3] Ouellet, S., Bussière, B., Aubertin, M., Benzaazoua, M. 2007. Microstructural evolution of cemented paste backfill: Mercury intrusion porosimetry test results. Cement and Concrete Research, Cilt. 37, No. 12, s. 1654-1665. DOI: 10.1016/j.cemconres.2007.08.016
4. [4] Bertrand, V.J., Monroy, M.G., Lawrence, R.W., 2000. Weathering characteristics of cemented paste backfill: mineralogy and solid phase chemistry. In Proceedings from the 5th international conference on acid rock drainage, 863-876.
5. [5] Tariq, A., Nehdi, M. 2007. Developing durable paste backfill from sulphidic tailings. Waste and Resource Management, Cilt. 160, No. 4, s. 155-166. DOI: 10.1680/warm.2007.160.4.155
6. [6] Cihangir, F., Ercikdi, B., Kesimal, A., Turan, A., Deveci, H. 2012. Utilisation of alkali-activated blast furnace slag in paste backfill of high-sulphide mill tailings: effect of binder type and dosage. Minerals Engineering, Cilt. 30, s. 33-43. DOI: 10.1016/j.mineng.2012.01.009
7. [7] Ercikdi, B., Külekci, G., Yılmaz, T. 2015. Utilization of granulated marble wastes and waste bricks as mineral admixture in cemented paste backfill of sulphide-rich tailings. Construction and Building Materials, Cilt. 93, s. 573-583. DOI: 10.1016/j.conbuildmat.2015.06.042
8. [8] Yin, S., Shao, Y., Wu, A., Wang, Y., Chen, X. 2018. Expansion and strength properties of cemented backfill using sulphidic mill tailings. Construction and Building Materials, Cilt. 165, s. 138-148. DOI: 10.1016/j.conbuildmat.2018.01.005

9. [9] Zheng, J., Guo, L., Sun, X., Li, W., Jia, Q. 2018. Study on the strength development of cemented backfill body from lead-zinc mine tailings with sulphide. Advances in Materials Science and Engineering, DOI: 10.1155/2018/7278014 (In Press).
10. [10] Xenidis, A., Mylona, E., Paspaliaris, I. 2002. Potential use of lignite fly ash for the control of acid generation from sulphidic wastes. Waste Management, Cilt. 22 No. 6, s. 631-641. DOI: 10.1016/S0956-053X(01)00053-8
11. [11] Tozsin, G., Arol, A.I., Oztas, T., Kalkan, E. 2014. Using marble wastes as a soil amendment for acidic soil neutralization. Journal of environmental management, Cilt. 133, s. 374-377. DOI: 10.1016/j.jenvman.2013.12.022
12. [12] Ercikdi, B., Cihangir, F., Kesimal, A., Deveci, H., Alp, İ. 2009. Utilization of industrial waste products as pozzolanic material in cemented paste backfill of high sulphide mill tailings. Journal of hazardous materials, Cilt. 168, No. 2-3, s. 848-856. DOI: 10.1016/j.jhazmat.2009.02.100
13. [13] Türker, P., Erdoğan, B., Katnaş, F., Yeğinobalı, A. 2009. Türkiye’deki Uçucu Küllerin Sınıflandırılması ve Özellikleri. Türkiye Çimento Müstahsilleri Birliği (TÇMB), AR-GE Enstitüsü, Ankara, s. 114.
14. [14] ASTM C618-17a, 2017. Standard Specification for Coal Fly Ash and Raw or Calcined Natural Pozzolan for Use in Concrete. Annual Book of ASTM Standards, ASTM International, West Conshohocken, PA.
15. [15] ASTM C39/C39M−16b, 2016. Standard Test Method for Compressive Strength of Cylindrical Concrete Specimens, Annual Book of ASTM Standards, ASTM International, West Conshohocken, PA.
16. [16] ASTM D4404-10, 2010. Standard Test Method for Determination of Pore Volume and Pore Volume Distribution of Soil and Rock by Mercury Intrusion Porosimetry, Annual Book of ASTM Standards, American Society of Testing Material.
17. [17] IUPAC, 1972. Manual of Symbols and Terminology. Appendix 2-Part 1: Colloid and Surface Chemistry, Journal of Pure and Applied Chemistry. Cilt. 31, s. 578–593. DOI: 10.1351/pac197231040577
18. [18] Wang, X.Y., Park, K.B. 2015. Analysis of compressive strength development of concrete containing high volume fly ash. Construction and Building Materials, Cilt. 98, s. 810-819. DOI: 10.1016/j.conbuildmat.2015.08.099
19. [19] Memon, A.H., Radin, S.S., Zain, M.F.M., Trottier, J.F. 2002. Effects of mineral and chemical admixtures on high-strength concrete in seawater. Cement and Concrete Research, Cilt. 32, No. 3, s. 373-377. DOI: 10.1016/S0008-8846(01)00687-1
20. [20] Shaikh, F.U.A, Supit, S.W.M. 2015. Compressive strength and durability properties of high volume fly ash (HVFA) concretes containing ultrafine fly ash (UFFA). Construction and building materials, Cilt. 82, s. 192-205. DOI: 10.1016/j.conbuildmat.2015.02.068
21. [21] Yumlu, M. 2001. Backfill Practices at Cayeli Mine. 17th International Mining Congress and Exhibition of Turkey, 19-22 June, Ankara, 333-339.
22. [22] Belem, T., Benzaazoua, M. 2004. An overview on the use of paste backfill technology as a ground support method in cut-and-fill mines. 5th International Symposium on Ground support in Mining and Underground Construction, 28-30 September, Perth-Western Australia, 637-650.
23. [23] Yilmaz, E., Belem, T., Bussière, B., Benzaazoua, M. 2011. Relationships between microstructural properties and compressive strength of consolidated and unconsolidated cemented paste backfills. Cement and Concrete Composites, Cilt. 33, No. 6, s. 702-715. DOI: 10.1016/j.cemconcomp.2011.03.013
24. [24] Abdul-Hussain, N., Fall, M. 2011. Unsaturated hydraulic properties of cemented tailings backfill that contains sodium silicate. Engineering geology, Cilt. 123, No. 4, s. 288-301. DOI: 10.1016/j.enggeo.2011.07.011